Lamp dimmer



June 8 1926.

c. w EISELE LAMP DiMMER Filed Oct. 14, 1921 ATTORNEY.-

Patented June 8, 1926.

, g 1,588,319 PATENT OFFICE.

CHARLES w. n'IsnLE, or FLINT, MICHIGAN.

LAMP DIMMEB.

Application filed October 14, 1921. Serial No. 507,711.

My invention relates to lamp dimmers or anti-glare devices for vehicle head lights. his the invention 15 designed for embodiment in lights for automobiles, motor boats,-

tractors, locomotives and railway cars, it may be adapted to lamps for other purposes. The present invention is a further development and amplification of the invention disclosed in my Patent No. 1,335,727, issued April 6, 1920, and particularly an amplification and continuation of the disclosure of Letters Patent No. 1,426,162, dated August 15, 1922. This invention contemplates a head light of the usual type, comprising an incandescent bulb located within a parabolic or concave reflector, in combination with a solenoid having a hollow or tubular shield or sleeve, adapted to beintermittently projected toa position within the refiector' to intercept the rays of light which would otherwise be reflected as is shown in my co-pending application aforementioned. The present invention embodies new and novel means of locking or temporarily restraining the reciprocatory hollow solenoid core in its assumed position at the opposite limits of its stroke.

The object of the invention is to simplify the structure as well as the means and mode of operation of lamp dimming or antiglare devices, whereby they will not only be cheapened in construction, but will be more complete in use, uniform in action, positive in operation, easily controlled, and unlikely to get out of order. I

A further object of the invention is to improve the control means for the reciprocatory action and to provide automatic locking means therefor for temporarily restraining the movable element, at either limit of its stroke.

A further object of the invention is to eliminate the use of springs as in my prior constructions before mentioned.

With the above primary and other incishowing the interceptor or sleeve in its advanced position, the relative position of the solenoid or electromagnetic coil by which the interceptor is controlled. Fig. 3 is an enlarged detail sectional view of the interceptor or tubular sleeveand control means therefor. Fig. 4 is a transverse sectional view on line 44 of Fig. 3.

' Like parts are indicated by similar characters of reference throughout the several views. 3 1 1 Referring to the preferred form of embodiment of the invention shown in the drawings, 1 is a lamp housing having'the usual transparent glass2. The transparent glass 2 is carried in frame 3,which forms a removable closure for the housing 1. Within the housing 1 is located a reflector 4 of the customary concavejform, having positioned therein an incandescentcelectric lamp bulb or other illuminating element 5. The

of light emanating fromthe bulb or illuminating device 5 are reflected from the. inner face of the concave reflector 4. The reflector 4 is so proportioned that the rays of light will be condensed in the field of illumination and will be projected in substantially parallel rays as isusual in lamps of this character. However, the particular form of the reflector 4 and its light reflecting function, per se, form no part of the present invention; 1 i I Without the reflector 4 the illuminating element 5' affords but a limited degree of illumination. Therefore by intercepting the rays of light emanating from the lamp and permitting ,only a limited portion of the light rays to reach the reflector 4," the brilliancy or intensity of illumination may be varied. p p

In the present instance as also in my preceding construction referred to, this inter ception of the light rays and consequent reduction of brilliancy is effected by the reciprocation of a tubular shield or interceptor whichv in its forward position encloses the lamp bulb or illuminator 5, preventing the rays of light therefrom from reaching the reflector 4, while in its retracted position it exposes the lamp bulb allowing it to function normally in relation with the reflector.

Whereas in my prior constructions, this interceptor or tubular shield hasbeen spring actuated in one direction, .and electrically operated in the opposite direction against the tension of such spring, in the present construction, the spring is entirely omitted, and the tubular interceptor is actuated in alternate directions by an electromagnetic influence.

Mounted intermediate the housing 1 and reflector 4, and in axial alinement ztherewith is a :solenoid, :having two" windings -,:7 and 8. This solenoid is supported at its rear :end ,upon a spider 9, or :collar having radially inclined cars '10 ifor attachment to the hous- 1m '1. Art its forward end the solenoid is supported 'by an "extension 11 of the spool upon which the coilis wound, which {exten- 'sion 11 engages in -an opening at .the ;.center or ape of the reflector 4:. The interior of the solenoid core is of comparatively large diameter. Extending :aXia'll-y :therethru is astem 12 'forathe lamp bulb :5. This stem foriconvenience:andieconomy ofzmanufacture has been shown :as a length of tubving, iperi pherally fianged at its rearward end 'for engagement with the supporting collar or spider 9. At :its forward end it carries the usua l lamp -socket :13 for the engagement of the bulb 5. Mounted for ree'iprocaitory movement within the double wound solenoid is the tubular or hollow-core 1'4, to the forward 'end'o'i' which is attached a tubular extension 15 of aluminum, fibre or other nonmagnetic material, which oomprises the shield or interceptor, surrounding "the damp bulb '5, when "the eore is ;actu ated torwardly. The solenoid eore let and shield or "interceptor 15 are fixedly connected-one to the-other and movedin unison, under the -influ'ence of the; solenoid windings 7 8. "The arrangement is such that when the winding? is connected in ci'reu'it,

' the tendency of the tubular solenoid 14 to assume a "balanced or symmetrical relation with the windings 7, thrusts the tubular shield or'interceptor 1'5 forwardlyfto a p osition enclosing the light bulb as show-n in Fig. '2 and by-dotted lines in Fig. '3. Likewise upon elosing the*eircuit-thruthe winding 8, the like tendency of the l1e'llow-core 14 -to assume symmetrical relation with the coils retracts the interceptor 15 thereby exposing the bulb. Inasmuch as it would be a matter of inconVen-ienceand' also waste as of electrical energy to maintain a constant circulation of current t'hru one or the other of athe "windings '7 and 8 to hold the core '14 in its adjusted position, means is provided 'for temporarily "locking the core at either limit of its stroke and hence =maintainingthe shield or interceptor 1'5 in either retracted or operative position. To this end the core 14 is prov-ided with a head or internal flange 16. Formed in the head 16 area plurality of radially vdisposed bores 17., in :each of whieh is located a spring pressed ball 18, yieldingly mounted within such bore and projecting somewhat beyond thei'nner ends'th'ereo'f. The central stem or support 12 for the lamp is provided at a medial point with a peripheral bead 19, over which the detent balls 18 of the solenoid core ride upon its rearward movement. This peripheral head or convex :enlargement'of thesupporting stem12 is so positioned that vtheidetent balls 18 will engage immediately behind'such enlargement when ithe core 14 is retracted. The spring tension-oi the balls 18 serve to retain the core in its retracted position, preventing its displacement by the jar and vibration ofithe vehicle. However, the :tension of these retaining balls is such that the influence of the winding 7 is sufficient to overcome the :res'istence of detent balls 18 causing them .to ride over the peripheral Fbead or obstruction 19., ".38 the core is drawn forwardly. Adjustably mounted upon the forward end of the lampsupponting 'stem :12 is a tapered collar :20 having therein a {peripheral groove. 21, within "which the detent balls 18 engage at the forward limit :0 f their -movement. The collar :20 enay be i'fiezediy mounted upon the s-stem '12, abut is preferably screw zthreaded thereon to .enable :its adjustment for varying the extent of imovementlof :the core :14. .As the core 1.4L approaches the forward limit of its movement under the influence :of therwinding 7, the vrretainiingg balls :18 will vride up the :inclined surface of the collar 20, against the tension of their :springs and seatuvithin the peripheral groove :21, thereby temporarily locking the core :in its :advanced :position. The collar 20 is provided with'a peripheral flange 22, which limits the forward movement of the core under the influeneeo'f the winding. Adjacent to this stop flange 22 there is positioned a collar'23 o'f fibre, rub

her :or other material to receive the impact of'ithe core and cushion :its arrest. A similar gasket or collar'2 i is provided =adja'cent to \the supporting collar or spider '9 to ousl'lio'n the retrograde impingement of the core.

"The so'lenoid windings 7 and 8 maybe controlled by separate push buttons or switches to momentarily close the circuit therethrough to actuate the core in opposite directions. 7 To prevent both windings 7 and 8 being simultaneously interconnected with the source of electrical energy, there has been show-11 a preferred form of-control switch comprising a suitable housing 25, within which is located a pivoted switch 'bar 26, carrying two plunger stems 27,=each the bar in its balancedposition. The pivoted switch bar 26 is connect-ed through battery or other source of electrical energy with both windings 7 and 8. Adjacent to each end or" the switch bar 26 are contacts '29 and 30 connected respectively to the windings 7 and 8. By pressing one of the plunger stems 2'! to oscillate the switch bar- 26 into engagement with one of such contacts, the spring surrounding the other plunger stem is placed under compression and serves to return the switch bar to break the connection upon the release of pressure.

By such constrction it is impossible to connect both windings at the same time. The connection is automatically broken upon the release of the pressure of the operators finger.

In order that the driver may observe the side of the road toward which he must turn in passing an approachin vehicle and to safeguard against dangers and obstructions in the roadway when the lamps are dimmed by the advance of the shield or interceptor 15, such shields or interceptors are provided with small openings 31, so positioned as to cast a restricted beam of light upon the interior of the reflector 4. To maintain the shield in position the solenoid core 14 is splined within the here or passage of the solenoid core to prevent relative rotation thereof. In order that the friction may be reduced to minimum, the spline or key comprises the spring pressed ball 33 similar.

to the balls 18 in a bore 34; quite similar to the bores 17. The ball 33 engages in a longitudinally disposed groove or key way 35 in the shell or spool of the coil. I The ball 34C is pressed outwardly into such key way or spline and while permitting free longitudinal movement of the solenoid core, it effectually prevents rotation thereof.

From the above description it will be apparent that there is thus provided adevice of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

lVhile in order to comply with the statute the invention has been described in language more or less specific as to structural features it is to be understood that the invention is not limited to the specific details shown, but that the means and construction herein disclosed comprises the preferred form of several modes of putting the invention into effect, and the invention is lamp coacting with the reflector, an electro magnet axially mounted in relation with the reflector, a reciprocatory tubular shield controlled by the electromagnet intercepting the light rays in one position of adjustment, and detent means tending to restrain the shield at the opposite limits of its movement.

- The combination of a lamp and a shield relatively movable in relation with the lamp, a solenoid to the core of which said shield is connected for unison movement, said solenoid including two windings to'be alternately energized to move said core, first in one direction and then in the other, and

spring meanstensioned by the movement of the core for yieldingly restraining the movable shield at the oppositelim'its of its range of movement.

4. In combination, a reflector, a lamp coacting therewith, a shield shiftable upon the axis of the reflector into and out of position to intercept light rays directed toward the reflector, a solenoid having two coils in tandem, and a core common to both coils to which the shield is connected, and means for alternately energizing the solenoil coils and yielding spring means tensioned by the movement of the solenoid core, the reaction of which yieldingly restrains the shield at the opposite limits of its movement. v

5. The combination with a reflector of a lamp, and an interceptor for light rays directed toward the reflector, the interceptor being relatively movable, in relation with the lamp, of a solenoid having coils in tandem controlling the movable interceptor, which is shifted to operative position by the influencev of one coil and retracted by the influence of the other coil,the movable interceptor being fixedly attached to the core of the solenoid for reciprocatory movement in unison therewith, and spring detent means for yieldingly restraining the core at the opposite limit of itsmovement.

6. The combination with alamp and an interceptor for rays of light therefrom,

which interceptor is movable in relation with the lamp, of a solenoid having coils in tandem, controlling the movable interceptor which is shifted to operative position by the influence of one coiland retracted by the influence of the other coil, and spring detent means for the movable interceptor tending core common to both windings, :and :detent means for locking the core at the opposite limits-oi its range of movements.

8. In a construction of the character described, the combination with an illuminating element and a shield movable relative thereto, '01 actuating means therefor including -.a solenoid having tandem windings, a core common to both windings, a yielding plunger'carried by the core, a member ali-ned With the direction of travelot' :the core having deflections in the surface thereof with which the plunger ei'igages as the core approaches the limit of its movement to :temporaril-y restrain the core in its operated position. 1

9. In a construction of the character deserlbed, the combination With an :11luminatrngelement and a shleldmovable relative thereto oI actuating 'means therefor including a solenoid, a core therefor, having a ball yieldingly mounted thereimand stop means yieldingly engaged by the ball as the core approaches the limitoi its movement in either direction to restrain the core in its adjusted position. 7

10. In a construction of the character described, the combination with an lilluminating element and a shield inovablerelative thereto,-ot an actuating means therefor including a solenoid, a core therefor, the sleeve of the solenoid being provided With an internal longitudinally disposed spline, and a ball seated in the core and engaging in saidspline to :prevent relative rotationof the core and the coil of the solenoid.

In testimony whereof, I have hereunto set my hand this ith day or October A. D. 1921.

CHARLES \V. E-ISELE. 

